The invention applies to an electrical primer for projectiles with an electrical igniting element and with an ignition switch arrangement with at least one storage condenser which may be connected to the ignition element via an electronic switching element.
An electrical projectile primer of the type mentioned is already known (DAS 1 155 037). This primer contains a storage condenser which can be charged by means of a voltage source and which is connected, via a charging resistor, to an ignition condenser. The ignition condenser is switched in parallel with the electrical ignition element. In this way a voltage dependent circuit element in the form of a semiconductor diode is switched between the ignition condenser and the ignition element. When the diode attains a certain voltage, it extends to the ignition condenser, so that the charge of the ignition condenser can flow through the ignition element to ignite the primer.
In the case of primers with longer running time, it is necessary to use condensers of considerable size which make it difficult to apply them to projectiles of small caliber. In addition, the safety of the primer before and during firing is unsatisfactory. The purpose of the invention is to create an electrical primer of the type mentioned which requires only condensers of relatively low capacity and therefore can be produced with small dimensions and which furthermore provides a higher degree of safety. According to the invention, this is achieved in that the electronic switching element is an electronic coupling element which is provided with an input control, and further, that an electrical pulse generating time element is connected to the input control of the electronic triggering device.
In the case of this primer of this invention, it is no longer necessary that there be a transfer in the charge from a storage condenser, chargeable from an outside voltage source, to an ignition condenser. This transfer is only possible in an incomplete manner. The ignition storage condenser of the present invention can be charged directly so that this charge is fully available for ignition.
By means of the use of an electronic triggering device provided with an input control and the utilization of a timing element generating electrical pulses, it is possible to obtain relatively long delay periods. Furthermore, the primer of this invention makes it possible to use proven mechanical construction elements, such as those disclosed in German Patent No. 1,126,776; German Patent No. 977,787; German disclosure 1,578,483; and German disclosure 1,924,025. Preferably a control storage condenser charged by impulses is connected in series to the triggering element. The control storage condenser can be connected in parallel to the series combination of the discharge resistor and a switching device controlled by the timing element. For this purpose a controllable electronic circuit element can be provided as a switching device.
An electronic oscillator circuit can be provided as the timing element fed by another storage condenser. However, a mechanically driven rotary oscillator, preferably a balance wheel, can also be provided as the timing element.
A coil arrangement and a permanent magnet arrangement influencing the coil arrangement and movable with respect thereto may be provided for controlling an electronic circuit element. In case a mechanically operated rotary oscillator is used, the coil arrangement or the permanent magnet arrangement can be attached to this rotary oscillator.
However, as the timing element, one may also use a mechanical driving gear equipped with a braking control released by a plate spring. In this case the coil arrangement or the permanent magnet arrangement can be placed at the release plate spring. For the purpose of controlling the controllable electronic circuit element, it is also possible to use a piezoelectric crystal which is connected to the release plate spring.
Preferably a safety circuit is connected to the ignition circuit which preferably separates the igniting element from the ignition circuit in a bipolar manner, whereby an acceleration driven or centrifugal force driven safety element is provided which, after firing of the projectile, activates the safety circuit to switch the igniting element into the ignition circuit.
An activating element under spring action, blocked by the safety element, can be connected to the safety switch, whereby the activating element can be provided with a starting device for the timing element. This starting device may be a starting spring for a rotary oscillator. When an electronic oscillator circuit is used as the timing element, the starting device may also be a switching device to activate this oscillator circuit.
The primer of the present invention is suitable both for rifled projectiles and for smooth bore projectiles such as rockets.
A high degree of accuracy in setting the fuse can be achieved with the primer of this invention. In conjunction with additional mechanical safety devices, one obtains a primer which is extremely safe to handle and quick to operate.
It is accordingly a general object of the present invention to obviate many of the deficiencies of known primers and to provide a novel primer and method of priming a projectile.
These and many other objects and advantages of the present invention will become apparent to one skilled in the art to which the invention pertains from the claims and from a perusal of the following detailed description when read in conjunction with the appended drawings.